Underfeed stoker



May 17, 192?.

' 1,629,282 E. LU N DG R EN v UNDERFE'ED STOKER Filed April 19. 1925 2Sheets-Sheet 1 A TTO NE YS 1,629 282 May 17 1927' E. LUNDGRl-:N

UNDERFEED ySTOKER Filled April 19, 1925 2 sheets-sheet 2 I N VEN TORATTORNE ifs lec i any iv, isa?.

EDWIN LUNDGREN, or FREDRICK, MARYLAND, Assrenoia To coiriBUstrIoirElisi- NEERi-NG CORPORATION, or NEW Yognx, N. Y., A. conroaa'rion' orNew Yoan.

UNDERFEED STOKER.

applica/aun mea april le, 1923. serial No. saaoes.

My invention relates to underfeed stokers and more particularly tounderfeedstokers of' the inclined' multiple retort type.

rlhe principaobj'ctof the invention is to provide novel and improvedmeans for controlling the admission of air to the air supplying surfacesof the underfeed section of stokei's of the type above indicated.

The following is a description of my invention, reference being had tothe accompanying drawings, in which,-

Figure l is a longitudinal sectional View of a portion of an underfeedstoker embody-v ing the features of the invention in their preferredform; l

Fig. 2 is a transverse sectional view, on an enlarged scale, taken onthe line 2-2 of Fig. 1; l

Fig. 3 is a longitudinal sectional view'of a portion of an underfeedStoker having a modified form of means for controlling the supply of airto the'fuel supporting surfaces; Fig. 4 is a transverse sectional view,on an enlarged scale, taken on the line 4-4 of Fig. 3;,and

Fig. 5 is a p component part of 'the structure shown 1n Figs. 3 and 4. A

The Stoker illustrated in the drawings 1s provided with a plurality ofdownwardly iuclined fuel re'toits 2 and tuyre boxes 4 alternatelyarranged, and a wind box 6 located beneath the fuel retorts and tuyreboxes for supplying air to the tuyre boxes. lhe retorts 2 are eachprovided with a bottom wall 8 and vertical side walls 10, the .latteralso constituting the side walls of'the tuyre boxes. The upper andloweredges of each of the side walls 10 are rovided with flanges 12 and14, respective that project 1nwardly toward the centers of the tuyreboxes. A series of tuvre blocks 16 is supported on the-flanged upperedgesv of the l side walls 10 so as to form the tops of the tuyreboxes.A

In the fonstruction illustrated in Fig. 1, each tuyre box is providedwith upper and lower end walls 18 and 20, respectively, and' with threetransverse partitions 22 that divide the tuyre box into fourcompartments.

detail view in perspective of a side of the three upper compartments ofeach tiiy'ie` box, and the opening in the under side ofthe loweimostcompartment is partially closedbyfa suitably .curved Wall vor bailleplate 26. l It will be apparent thatvby varying the relative width ofthe. base portions of the partitions and the plate 26, the supply of airto the several .groups of tuyre blocks may be relativelyvaried asdesired. One advantage of this provision for' controlling the supply ofair to the several groups of tuyre blocks of each individual tuyre boxis vthat dierent kinds of fuels'require dierent air supply underdifferent parts ofthe fuel bed. For instance, when bituminous fuels areburned in a stoker of tlstype, a gradually decreasing air supply towardthen rear end of the Stoker is desired, but when burning Waste fuels,such as coke breeze, or low grade fuels such as lignite, the opposite is'desired Also this. construction permits individual control ofv air tovbe secured lfor each tuyre 'box which is 'of particular advantage inrelatively wide stokers.

As shown', the partitions 22 are removably mounted on the flanges 14 andare adapted vto be relatively adjusted longitudinally of -the flangeswithin certain limits, so as to vary the number of tuyre blocks in each.of said groups. To provide for this the base portions 24 of thepartitions are provided with depending lugs 28 that are adapted to bereceived in a Series of notches 30 in each of the flanges 14. Ifdesired, however, the partitions 22 may be cast integral with the sidewalls of the tuyre boxes.

The su ly of air to the di'erent groups of tuyre ocks may alsobe variedby means of transverse battles or air obstructing plates 32 that areremovably mounted on the flanges 14 and are adapted to be adjustedlongitudinally of the flanges by means of dedesirable in some cases when'it is desired to adjust the partitions 22.

In theconstruction illustrated in Flgs,

4vand 5 of the drawings each tuyre box is.

provided with three partitions 36 that divide the box into fourcompartments that are similar to the compartments of the constructionillustrated in Fig. l. The openings in the under sides of thesecompartments are partially closed by transverse baffle plates 38, and asliding damper 40 is arranged to slide longitudinally along the undersides of the transverse plates 38. The damper 40 is provided withtransverse portions 42 which are so positioned with relation to the bars38 that when the damper is in its extreme lowermost position, as shownin Fig. 3 of the drawings, a greater supply of air will be admitted tothe uppermost than to the lowermost compartment and that upon slidingthe damper to its extreme upper position the opposite result is secured,`the supply of air to the intermediate compartments being variedaccordingly. The .damper for each tuyre box is .adapted to beconveniently operated outside of the furnace, by means of a rack` 44 onthe under side of each damper which is engaged by a pinion 46 on theinner end of a shaft 48 that extends through the outer wall .of thefurnace and is provided with an operating crank 50 on its outer end.

In the constructionv illustrated in Fig. l the wind box is divided intotwo compartments by means of a transverse. partition 52 and air isseparately supplied to these com partments through ducts 54,respectively, having controlling dampers 56. This construction permits ahigher air pressure to be secured in the front compartment than in therear or vice versa, air being supplied to the ducts 54 under differentpressures.

As will be evident to thoseskilled in the art my invention permits ofvarious modifications Without departing from the spirit thereof or thescope of the appended claims.

What I claim is:

l. An underfeed stoker having, in combination, a plurality of downwardlyinclined fuel retorts and tuyre boxes alternately arranged, the tuyreboxes having fuel supporting tuyres, and means for relatively varyingthe supply of air to different groups of tuyres of one tuyre boxindependently of the other tuyre boxes.

2. An underfeed Stoker having, in combination a plurality of downwardlyinclined .fuel retorts and tuyre boxes alternately arranged, the tuyereboxes having fuel supporting tuyres, partit-ions dividing each tuyre boxtransversely into a pluralit of conxpartments, and means for relativelyvarying the supply of air to different compartments of one tuyre boxindependently ot' the other tuyre boxes.

3. An underfeed stoker having, in combination, a plurality of downwardlyinclined fuel retorts and tuyre boxes alternately ar-v ranged, thetuyere boxes having fuel supporting tuyres, and means comprisingpartitions within each tuyre box for controlling the supply of air todifferent groups of tuyres, said partitions being adapted to beindependently adjusted longitudinally of the tuyre boxes.

4. An underfeed Stoker having, in combination, acplurality of downwardlyinclined fuel retorts and tuyre boxes alternately arranged, the tuyreboxes having fuel supporting tuyres, and means for controlling thesupply of air to different groups of tuyres of each tuyre boxindependently of the other tuyre boxes comprising transverse partitionsin each tuyre box, and air obstructing plates extending betweenlongitudinal sides of each tuyre box and positioned between thepartitions.

5. An underfeed stoker having, in combination, a plurality of downwardlyinclined fuel retorts and tuyre boxes alternately arranged, the tuyreboxes having fuel supporting tuyres, and means for supplying air underdifferent pressures to different groups of tuyres, respectively, of onetuyre box independently of the other tuyre boxes.

6. An underfeed stoker having, in combination, a plurality of downwardlyinclined fuel retorts and tuyre boxes alternately arranged, the tuyreboxes having fuel supporting tuyres, partitions transversely arranged ineach tuyre box dividing the tuyre box -into a plurality of compartments,a wind box located beneath the retorts and tuyre boxes for supplying airto the tuyres through openings in the under sides of said compartments,and means vfor relatively varying the size of said openings in saidcompartments so as to relatively vary the supply of air to saidcompartments of each tuyre box independently of the air supply to theother tuyre boxes.

7 An underfeed stoker having, in combination, a pluralityY of downwardlyinclined fuel retorts and tuyre boxes alternately arranged, the tuyreboxes having fuel supporting tuyres, and means for controlling thesupply of air to different groups of tuyres of each tuyre box comprisingtransverse partitions in each tuyre box having laterally extending airobstructingjbase portions, and air obstructing plates positioned betweensaid partitions and removably mounted on the lower longitudinal edgeportions of the longitudinal sides of said tuyre boxes.

8. An underfeed Stoker having, in combilll) llf

Leaaaea nation, a plurality of downwardly inclined fuel retorts andtuyre boxes alternately arranged, the tuyre boxes having fuel supportingtuyres, a transverse partition dividing each tuyre box into twocompartments, a wind box beneath the retorts and tuyre boxes, apartition dividing the wind box into two compartments, the twocompartments of each tuyre box being respectively in communication withthe two compartments of said wind box, and means for establishingcommunication between said compartments of the wind box and separatesources of compressed air supply, respectively.

EDWIN LUNDGREN.

